Occupational Exposure to 1,3-Butadiene

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DEPARTMENT OF LABOR

Occupational Safety and Health Administration

29 CFR Parts 1910, 1915 and 1926

[Docket No. H-041]

Occupational Exposure to 1,3-Butadiene

AGENCY: Occupational Safety and Health Administration (OSHA),

Department of Labor.

ACTION: Proposed Rule; Limited reopening of the rulemaking record.

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SUMMARY: The Occupational Safety and Health Administration is reopening

the record for the proposed revision of the 1,3-Butadiene (BD) standard

to solicit public comment on a joint labor/industry agreement dated

January 29, 1996, recommending that OSHA reduce the permissible

exposure limits and expanding on some provisions that were addressed in

OSHA's 1990 proposal (55 FR 32736, August 10, 1990). In addition, OSHA

is seeking comment on possible changes in the medical surveillance

requirements, including reliance on a medical questionnaire that would

replace some of the proposed yearly medical examinations and reduce the

need for medical removal protection. Finally, the Agency is entering

into the rulemaking record four documents that have become available

since the submission deadline of December 13, 1991, set by the

Administration Law Judge following the rulemaking hearings.

DATES: Written comments must be postmarked by April 8, 1996.

ADDRESSES: Comments are to be submitted in quadruplicate to the Docket

Office, Docket No. H-041, U.S. Department of Labor, Room N-2634, 200

Constitution Avenue, NW., Washington, DC 20210. Telephone (202) 219-

7894. Written comments limited to 10 pages or less in length may also

be transmitted by facsimile to (202) 219-5046, provided the original

and 3 copies are sent to the Docket Office thereafter.

Copies of the labor/industry agreement and submissions to the

record along with other information cited in this notice are available

for inspection and copying in the Docket Office. For electronic copies

of this notice, contact the Labor News Bulletin Board (202) 219-4784;

or OSHA's WebPage on the Internet at http://www.osha.gov/. For news

releases, fact sheets, and other short documents, contact OSHA FAX at

(900) 555-3400 at $1.50 per minute.

FOR FURTHER INFORMATION CONTACT:

Anne C. Cyr, Office of Information and Consumer Affairs, Occupational

Safety and Health Administration, U.S. Department of Labor, Room N-

3647, 200 Constitution Avenue, NW., Washington, DC 20210. Telephone

(202) 219-8148.

SUPPLEMENTARY INFORMATION:

I. Background

A. History

The present OSHA standard for BD requires employers to ensure that

employee exposure does not exceed 1,000 ppm determined as an 8-hour

time weighted average (TWA) (29 CFR 1910.1000, Table Z-1).

In 1983, the American Conference of Governmental Industrial

Hygienists (ACGIH) classified BD as an animal carcinogen based on a

National Toxicology Program (NTP) animal study showing that BD caused

cancer in rodents. The ACGIH recommended that employee exposures be

reduced to or below 10 ppm (8-hr TWA). In 1984, the United Rubber,

Cork, Linoleum and Plastic Workers of America (URW), the Oil, Chemical

and Atomic Workers, and the American Federation of Labor and Congress

of Industrial Organizations (AFL-CIO) petitioned OSHA to issue an

Emergency Temporary Standard (ETS) of 1 ppm or less. OSHA denied the

petition for an ETS, but began collecting information in order to

institute rulemaking under Section 6(b) of the Occupational Safety and

Health Act. The Environmental Protection Agency (EPA) was also studying

the health hazards of BD. That agency's analysis found that BD was a

probable human carcinogen and that workplace exposures presented an

unreasonable risk of injury to human health. Because exposures to BD

occurred primarily in the workplace, EPA, in accordance with section

9(a) of the Toxic Substances Control Act, referred BD to OSHA to give

this Agency an opportunity to regulate the chemical under the OSH Act.

(50 FR 41393; October 10, 1985).

On August 10, 1990, OSHA issued a notice of proposed rulemaking (55

FR 32736) to address the significant occupational risks of BD-induced

health effects. The proposed rule required employers to reduce

occupational exposure to BD to 2 ppm as an 8-hour TWA and 10 ppm as a

15-minute short term exposure limit (STEL), and to institute ancillary

measures, such as employee training and medical surveillance, for

further protection of BD-exposed workers.

OSHA convened public hearings in Washington, DC, on January 15-23,

1991, and in New Orleans, Louisiana, on February 20-21-1991. The post-

hearing period for the submission of briefs, arguments and summations

was to end July 22, 1991, but was extended by the Administrative Law

Judge to December 13, 1991, in order to give participants time to

review new data on low-dose exposure submitted by NTP and a

quantitative risk assessment done by NIOSH.

B. The Labor/Industry Agreement

To assist OSHA in issuing a final rule for BD, representatives of

the major unions and industry groups involved in the production and use

of BD submitted a voluntary agreement reached by the parties dated

January 29, 1996, on provisions that should be included in the

standard. The letter transmitting the agreement was signed by J.L.

McGraw for the International Institute of Synthetic Rubber Producers,

Michael J. Wright for the United Steelworkers of America and Michael

Sprinker for the International Chemical Workers Union. The committee

that worked on the issues also included Joseph Holtshouser of the

Goodyear Tire and Rubber Company, Carolyn Phillips of the Shell

Chemical Company, representing the Chemical Manufacturers Association,

Robert Richmond of the Firestone Synthetic Rubber and Latex Company,

and Louis Beliczsky (formerly of the URW) and James L. Frederick of the

United Steelworkers. OSHA is pleased that labor and industry have

joined together to recommend regulatory requirements that can lead to

lower and less frequent exposures for employees who work with or near

BD.

The agreement proposes a significant change in the permissible

exposure limits, additional provisions for exposure monitoring, and an

exposure goal program designed to reduce exposures below the action

level. It also proposes other modifications to the scope, respiratory

protection, communication of hazards, medical surveillance, and start-

up dates sections of the final rule. The agreement also assumes that

items not specifically addressed in the agreement will remain as

proposed. OSHA reprints the provisions below in order to allow the

public an opportunity to provide the Agency with comments.

1, 3-Butadiene

Recommended Revisions to OSHA's Proposed Standard Scope and

Application: Exclude [from the final rule's coverage]:

1. Products with BD concentration of 0.1% or less by volume unless

objective data shows exposure could exceed the

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AL [action level] or STEL [short-term exposure level].

2. Storage, transportation, distribution or sale of BD in intact

containers or pipelines, except for labeling requirements and emergency

response provisions.

Definitions: Objective Data means monitoring data or mathematical

calculations or modeling based on the chemical and physical properties

of the material, stream or product.

Limits:

1. Action level (AL) of 0.5 ppm [parts per million] (ppm) as an 8-

hour TWA.

2. Permissible Exposure Limit (PEL) of 1 ppm as an 8 hr TWA.

3. Short Term Exposure Limit (STEL) of 5 ppm [sampled] for 15

minutes.

Exposure Monitoring:

1. Establish a baseline of at least 8 samples. The samples may be

taken in a single year, so long as at least one sample is taken in each

quarter, and no two are taken within 30 days of each other. The

employer may utilize monitoring data from the previous two years to

satisfy the initial monitoring requirement as long as [the] process has

been consistent.

2. After the baseline has been established, monitoring is

[required]:

a. Every 6 months if exposure exceeds PEL or STEL.

b. Annually if exposure is at or above the AL but below the PEL.

Additional Monitoring: May use direct reading instruments for any

spills, leaks, etc. to ensure that levels have returned to normal

following an emergency.

Employee Notification: Five (5) day [period for] employee

notification of sampling results.

Exposure Goal Program: The employer shall institute an ``exposure

goal program'' which attempts to limit exposure levels to or below the

action level. No exposure goal program is required if all exposures are

at or below the action level. The program shall include the following

controls, unless the employer can demonstrate that they will not be

feasible or effective.

a. A leak prevention, detection, and repair program.

b. A program for maintaining the integrity of local exhaust

ventilation systems.

c. The use of pump exposure control technology such as, but not

limited to, double-sealed or seal-less pumps.

d. Gauging devices designed to limit employee exposure, such as

magnetic gauges on rail cars.

e. Unloading devices designed to limit employee exposure, such as

vapor return systems.

f. Maintaining control rooms below the AL by use of engineering

controls.

Respirators:

1. Use when exposure may exceed PEL or STEL.

2. Fit testing as per ANSI standards.

3. Allow \1/2\ face negative pressure respirators for certain

applications.

Medical Surveillance:

1. Medical evaluations for all employees exposed above the PEL for

30 days or more, or above the AL for 60 days or more.

2. Medical evaluations for formerly-exposed employees whose work

history includes exposure as defined in (1) for 10 year or more, or

exposure above 10 ppm as an 8-hr TWA for more than 30 days in any past

year, so long as they continue to be employed by the employer

responsible for the exposure, or a successor owner.

3. An exam with respect to acute effects as quickly as possible in

the case of exposure from a significant release.

4. Appropriate exams for respirator wearers in accord with 29

C.F.R. 1910.134.

5. Medical evaluations include an update of medical history [and] a

CBC [complete blood count] including platelets. Additional tests are

deemed appropriate by the examining physician. Remove references to

fertility evaluations.

Communication of BD Exposure to Employees: Modify warning signs and

label requirements to eliminate reproductive/lung/kidney reference.

Employee Training: Required annually or with change of job when

exposure may reach PEL, STEL or AL.

Dates: Employer may take up to two (2) years from effective dates

to implement engineering controls.

Appendices: OSHA should also correct certain misstatements in

Appendices A and B:

Appendix A, Part IV(B): The sentence; ``Any clothing which becomes

wet with liquid BD should be removed immediately * * *'' should be

deleted. BD evaporates too rapidly to cause wet clothing.

Appendix B, Part II(A)(6): The statement that ``vapors of BD will

burn without the presence of air or other oxidizers'' is incorrect.

Appendix B, Part III(A)(3): The suggestion that spills of small

quantities of BD should be absorbed on paper towels is unnecessary, as

the BD will evaporate too quickly.

Appendix B, Parts VI (C) and (D): Sanitation requirements

concerning agents to remove BD from the skin, and separate lockers, are

unnecessary, since liquid BD evaporates rapidly and will not

contaminate skin or clothing for any significant time.

Not also the odor threshold discrepancy between Appendix B, Part

II(C) and Appendix D, Part 1.1.4. The correct value is 0.45 ppm, based

on the AIHA publication, ``Odor Thresholds for Chemicals with

Established Occupational Health Standards,'' (1989).

OSHA believes the agreement contains a number of provisions that

will greatly improve worker health and therefore should be included in

the final BD standard. However, prior to inclusion, the Agency must be

certain of the meaning and effect of the provisions and then translate

the recommendations into regulatory language. To this end, OSHA seeks

comment on the following issues addressed by labor and industry in

their agreement:

1. Definitions. When objective data are relied upon to exclude

products with a BD concentration of 0.1% or less, what should be the

source of the objective data? Should conditions be placed upon the

monitoring or modeling methods used to obtain or project exposure

levels in order to ensure accuracy?

2. Exposure Monitoring. OSHA is concerned that the taking of 8

samples to establish a baseline may not be an effective use of scarce

industrial hygiene resources in that the number of samples taken may be

far less important than the quality of the samples used to characterize

the exposure of BD employees. Are there other ways to improve OSHA's

traditional approach of monitoring at least the one most exposed

employee in each job classification on each shift? Please comment.

3. Exposure Goal Program. OHSA requests comment on whether the

requirements for specific engineering controls rather than a

performance approach could lead to situations in which (1) better

engineering controls are discouraged or ignored, (2) the required

controls may not be applicable, or (3) the required controls may not be

needed because work practices will achieve the necessary reduction. How

could these situations be avoided?

4. Respirators. ANSI does not have final protocols for respirator

fit-testing. OSHA is in the process of completing its generic

respirator standard that will include protocols for fit-testing. (OSHA

Docket No. H-049; 59 FR 5884, November 15, 1994). Do workers exposed to

BD need special provisions for respirator fit-testing? If so, what

provisions are necessary and why? What applications are appropriate for

half-mask negative pressure respirators? Should the standard specify

tasks or exposures where the respirators are or are not appropriate?

5. Medical Surveillance. OSHA is concerned that some at-risk

employees

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will not be afforded the protection of medical surveillance because

eligibility for inclusion requires exposures of 60 days above the AL or

30 days above the PEL, requirements that are more restrictive than the

comparable requirements in OSHA standards for acrylonitrile, (any

exposure above the AL); benzene, (30 days above AL or 10 above PELs);

and cadmium, (30 days above AL). OSHA also seeks comment on whether the

medical requirements in the respirator standard for general industry,

29 CFR 1910.134(b)(10), may be inadequate to protect workers with

occupational exposure to BD. In addition, should each employee whose

exposure to BD requires the use of a respirator be included in the

medical surveillance program, regardless of duration of exposure?

Finally, by requiring employees whose former exposures were above the

action level for 60 days or the PEL for 30 days to have had 10 years of

exposure before being included in medical surveillance, would the

standard improperly exclude employees whose exposures occurred over a

lesser period of time, say 5 years, but whose risk may be comparable?

6. Communication of BD Exposure to Employees. OSHA is concerned

that eliminating the reference to potential reproductive hazard from

warning signs and labels would not provide sufficient information to

employees. Toxicological studies cited in the proposal indicate BD is a

potential reproductive hazard. For example, ovarian atrophy and

testicular atrophy were observed in mice exposed to BD. OSHA is

considering requiring the warning signs and labels to contain the

phrase ``Cancer and Potential Reproductive Hazard.''

C. Additional Issues

OSHA is also seeking comment on the following issues that were

neither addressed by labor and industry in their agreement, nor fully

aired at the rulemaking hearing:

1. OSHA proposed to define ``Emergency'' as:

* * * any occurrence such as, but not limited to, equipment

failure, rupture of containers, or failure of control equipment that

may or does result in an unexpected significant release of BD.

OSHA is considering limiting the emergency releases to those that are

uncontrolled, so that the last phrase of the definition would read: ``*

* * that may or does result in an uncontrolled significant release of

BD.'' Does this addition clarify what situations OSHA considers to be

emergencies? Does the term ``significant release'' give adequate

guidance to employers as to how much BD must be released in order to

constitute an emergency?

2. OSHA is considering the adequacy of a less burdensome medical

surveillance program for BD-exposed workers. The program would consist

of an initial medical examination, repeated every third year, and an

annual CBC along with a yearly questionnaire focusing on the

hematopoietic and reproductive systems. OSHA requests comment on

whether this approach is sufficiently protective. OSHA is also seeking

comment on whether medical removal protection provisions similar to

those contained in the Benzene Standard (29 CFR 1910.1028) are

appropriate for BD. Removal would be predicated upon a medical

determination that the employee should not continue to be exposed to

BD.

3. Where employers rely on objective data to exempt them from

monitoring responsibilities, OSHA is considering requiring these

employers to keep the data for as long as such data continue to be

relied upon. Is this the appropriate length of time to keep such data?

D. Additional Submissions to the BD Docket

OSHA is submitting the following reports to the BD Docket:

(1) Abstracts from International Symposium: Evaluation of Butadiene

and Isoprene Health Risks, June 27-29, 1995, Blaine, Washington; (2)

Delzell, E., N. Sathiakumar, M. Macaluso, M. Hovinga, R. Larson, F.

Barbone, C. Beall, P. Cole, A Follow-up Study of Synthetic Rubber

Workers, October 2, 1995; (3) Santos-Burgua, C., G. Matanoski, S.

Zeger, L. Schwartz, ``Lymphohematopoietic Cancer in Styrene-Butadiene

Polymerization Workers,'' American Journal of Epidemiology, Volume 136,

1992, pp. 843-844; and (4) M. Sorsa, K. Peltonen, H. Vainio, and K.

Hemminki (eds.), Butadiene and Styrene Assessment of Health Hazards,

International Agency for Research on Cancer Scientific Publication No.

127, Lyon, France, 1993.

II. Public Participation

Comments

Written comments regarding the issues raised by this notice must be

postmarked by April 8, 1996. Four copies of these comments must be

submitted to the Docket Office, Docket No. HS-041), U.S. Department of

Labor, 200 Constitution Avenue, NW, Washington, DC 20210. Written

comments limited to 10 pages or less in length may also be transmitted

by facsimile to (202) 219-5046, provided the original and 3 copies are

sent to the Docket Office thereafter. All materials submitted will be

available for inspection and copying at the above address. Materials

previously submitted to the Docket for this rulemaking need not be re-

submitted.

III. Authority

This document was prepared under the direction of Joseph A. Dear,

Assistant Secretary of Labor for Occupational Safety and Health, U.S.

Department of Labor, 200 Constitution Avenue, NW, Washington, D.C.

20210. It is issued pursuant to section 6(b) of the Occupational Safety

and Health Act (29 U.S.C. 655), and 29 CFR part 1911.

Signed at Washington, D.C., this 5th day of March, 1996.

Joseph A. Dear,

Assistant Secretary of Labor.

[FR Doc. 96-5519 Filed 3-7-96; 8:45 am]

BILLING CODE 4510-26-M